Nanotechnology sensors detect salmonella in food

Scientists are using nanotechnology to develop new ways of detecting pathogenssuch assalmonella in our foods.

Public health experts estimate that each year, more than 11 million Canadians suffer from food-borne illnesses such as salmonella or, more rarely, listeriosis. Some cases are mild, but for the very young or old, or pregnant women, the effects can be severe.

The emerging field of nanotechnology the science of using particles tens of thousands of times smaller than the width of a strand of hair could help improve food safety.

Nanoparticles are being used to build devices that sense the DNA of microbes such as salmonella or listeria, said Dutch biotechnology researcher Frans Kampers of the Biotechnology Centre for Food and Health Innovation at the Wageningen Research Centre.

Currently, the food industry has norapid test for the pathogens.

"At the moment, the problem is you have to take a sample, put it onpetri dish and put in stove for one day or sometimesthree days (it depends on the pathogen you're looking for), and then you count the colonies and know whether or not there are these nasty microbes," Kampers said.

Package could indicate decay inside

Nanoparticles could also be used in packaging to signal when food has passed its best-before date. When perishable foods like lettuce or milk deteriorate in quality, volatiles are created that could be sensed using nanotechnology, he explained.

There's no risk to putting nanosensors in packaging, Kampers said, but it's important to label products with nanotechnology features, so people can choose whether to use or avoid them.

"We realize that we have to build trust with the consumer."

The technology exists in the lab now and it's only a matter of making it economical before arrives in grocery stores, he said.

Kampers is also investigating how nanotechnology can make donuts and other foods healthier. The process starts by replacing the inside of fat molecules with water, leaving the outside of the droplets and the taste and texture of the food unchanged. Since the fat has been taken out,there are fewer calories.

Nanotechnology could also be taken a step further by adding tiny nanotubes of nutrients such as omega 3 fatty acids to food that disguise any bitterness so the taste is unaffected, he added.